Venezuela's president Hugo Chavez has a respiratory infection after undergoing cancer surgery in Cuba and must have "complete rest" for the next few days, the government said.
The socialist leader is in a stable condition after being diagnosed with the infection on Monday, information minister Ernesto Villegas said on television, reading a government statement.
"It has been controlled," Mr Villegas said. "In the opinion of the doctors, this type of ailment is one of the consequences that appear with the greatest frequency in patients who have undergone complicated surgeries."
The infection appeared a week after a six-hour operation that the government has said involved complications.
"The medical team has said that President Chavez should have complete rest in the coming days and receive ... the prescribed medical treatment, with the purpose of maintaining the stability of his vital signs that he currently enjoys," Mr Villegas said.
Concluding the statement, he said: "Long live Chavez!"
The announcement came amid uncertainty and concern over the 58-year-old president's health. Mr Chavez has not spoken publicly since his December 11 surgery for an undisclosed type of pelvic cancer, his fourth cancer-related operation since June 2011.
His elder brother Adan planned to travel to Cuba to visit the president, the government newspaper Correo del Orinoco said. It also said that the president's father, Hugo de los Reyes Chavez, had plans to travel to Havana and that Mr Chavez's mother might go with him.
Against the backdrop of Mr Chavez's illness, many Venezuelans are talking about the possibility of a looming transition of power and a new presidential election. Before undergoing surgery, Mr Chavez designated vice president Nicolas Maduro as his chosen successor to take his place if necessary.
Mr Chavez is due to be sworn in for a new six-year term on January 10. Under Venezuela's constitution, if the president dies, is incapacitated or steps down, a new election would be held within 30 days.